EP0958427A1 - A method and equipment for manufacturing predetermined low bark content wood chips and a high bark content fuel fraction from wood chips with bark attached - Google Patents

A method and equipment for manufacturing predetermined low bark content wood chips and a high bark content fuel fraction from wood chips with bark attached

Info

Publication number
EP0958427A1
EP0958427A1 EP96934872A EP96934872A EP0958427A1 EP 0958427 A1 EP0958427 A1 EP 0958427A1 EP 96934872 A EP96934872 A EP 96934872A EP 96934872 A EP96934872 A EP 96934872A EP 0958427 A1 EP0958427 A1 EP 0958427A1
Authority
EP
European Patent Office
Prior art keywords
bark
wood chips
mechanical
chips
content
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP96934872A
Other languages
German (de)
French (fr)
Other versions
EP0958427B1 (en
Inventor
Veli SEPPÄNEN
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Valtion Teknillinen Tutkimuskeskus
Original Assignee
Valtion Teknillinen Tutkimuskeskus
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Valtion Teknillinen Tutkimuskeskus filed Critical Valtion Teknillinen Tutkimuskeskus
Publication of EP0958427A1 publication Critical patent/EP0958427A1/en
Application granted granted Critical
Publication of EP0958427B1 publication Critical patent/EP0958427B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
    • B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
    • B07B9/00—Combinations of apparatus for screening or sifting or for separating solids from solids using gas currents; General arrangement of plant, e.g. flow sheets
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
    • B07B—SEPARATING SOLIDS FROM SOLIDS BY SIEVING, SCREENING, SIFTING OR BY USING GAS CURRENTS; SEPARATING BY OTHER DRY METHODS APPLICABLE TO BULK MATERIAL, e.g. LOOSE ARTICLES FIT TO BE HANDLED LIKE BULK MATERIAL
    • B07B15/00—Combinations of apparatus for separating solids from solids by dry methods applicable to bulk material, e.g. loose articles fit to be handled like bulk material
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
    • D21B1/00—Fibrous raw materials or their mechanical treatment
    • D21B1/02—Pretreatment of the raw materials by chemical or physical means
    • D21B1/023—Cleaning wood chips or other raw materials
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/10—Biofuels, e.g. bio-diesel
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel

Definitions

  • the object of the invention is a method and equipment for manufacturing predetermined low bark content wood chips and a high bark content fuel fraction from wood chips with bark attached, which method incudes the following stages:
  • the above-mentioned type of manufacturing method is known from the international patent publication WO 93/25324.
  • the wood chips with bark attached are ground initially either with a special plate grinder, or with a vibrating cone crusher, when the bark separates from the wood chips and the size of the bark particles diminishes.
  • a grinder or a vibrating cone crusher is followed by pneumatic separation, especially to separate outer birch bark, after which sawdust is removed using a vibrating sieve.
  • the bark content has now dropped to considerably less than 10 %, when the final cleaning can be carried out using an optical sorter.
  • two optical sorters are used in series, but can, however, be replaced by a single more powerful device. The accepted fraction from the second optical sorter is led to grinding and the reject to the fuel fraction.
  • Figure 1 shows the method according to the invention, as a block diagram.
  • Figure 2 shows equipment according to the invention, as a plant diagram.
  • the wood chips with bark attached can be considered as having been obtained by conventional methods, using a known cutter.
  • the wood chips are cleaned in pre-separation 3, 4, 5, which comprises among, other things, magnetic devices for removing scrap iron and a pneumatic separator 4, 4' for removing stones and sand.
  • pre-separation oversize wood chips are separated by means of disc sieve 5, and in practice are most advantageously led to the fuel fraction, but if necessary they can be led, for example, to a crusher and then back to pre-separation.
  • the fraction accepted in pre-separation 3, 4, 5 is led to thickness sieving 6, which is intended to separate the thin wood chip fraction, generally less than 6 mm, from the part of the flow of wood chips travelling through the thickness sieve.
  • This part is led to the following stage, i.e. past mechanical bark separation 7.
  • Mechanical bark separation can take place by means of either a plate grinder, a crusher, or in a blade ring chipper, which has been shown to be the most advantageous, because it does not defibrate the wood material unnecessarily.
  • the mechanically processed fraction, together with the smaller fraction obtained from the bypass line, is led to pocket-roll sieve 9, which effectively removes the sawdust from the flow of material.
  • the accepted fraction is led to a pneumatic separator, to remove light birch bark, leaves, needles, and other easily airborne particles from the flow of material.
  • the pre-cleaned wood chips already have a bark content of less than 10 %, when it can be led to optical sorter 10, from which wood chips with a bark content of about 1 % can be obtained, even at a large yield.
  • Reject from the optical sorter is led through selection 15 in a regulated manner either to the fuel fraction, or back to mechanical processing. In order to prevent a so-called 'mad cycle', 20 - 100 % is always led to the fuel fraction, and only 80 - 0 % is led to the mechanical processing. Certain species of timber or other conditions will mean that there is not necessarily any benefit from mechanical processing, in which case it is better to lead the reject from the optical sorter directly to the fuel fraction.
  • the plant diagram, Figure 2 shows cutter 1 and reception funnel 2, in which the wood chips are collected, or into which wood chips from external sources are poured. From here the flow of wood chips is led through magnetic separator 3 to disc sieve 5. Between these there is a pneumatic separator 4', which removes stones and a second pneumatic separator 4, which sucks light birch bark, leaves, and fine dust into the airflow, see also stone store 3.1.
  • a disc sieve 5 removes oversized pieces from the wood chips, which are led to the fuel fraction 13, together with reject from the pneumatic separator. Beneath the disc sieve there is thickness sieve 6, which separates the smallest fraction and the sawdust in it, these being led to mechanical bark separation, going past grinder 7, whereas the rest of this part is led to grinder 7.
  • the accepted fraction is led to optical sorter 10, from which a good yield of good quality cellulose wood chips 12 are obtained.
  • the reject is led through selection member 15 either to the fuel fraction 13 or to the grinder 7.
  • selection member 15 0 - 100 % can be taken from the flow of materials into the fuel fraction. It is advantageous to take at least 20 %, to prevent a so-called 'mad cycle' in the process. With certain grades of wood chips part of the material would remain to circulate continuously through the process, unless part of the reject is removed to the fuel fraction. All of the removed rejects are led in the Figure to fuel fraction 13, by means of conveyor 16.
  • the optical sorter uses a pneumatic conveyor, the reject flow is not homogeneous.
  • a divider plate 18 set in the exit area can separate the part with the greatest bark content from the rest of the reject, it then being advantageously led directly to the fuel fraction with the aid of conveyor 19. The figure shows this alternative by broken lines.
  • the pulverization of the wood is reduced with the aid of the method according to the invention, which increases the cellulose chip yield from the previous yield by 5 - 10 percentage units, while share of the fraction of cellulose chips remaining in the 13 mm particle size perforated sieve increases substantially (by 15 - 35 percentage units) .
  • a thickness sieve is used to separate the fraction with the desired value, 4 - 8 mm, for example, thinner than 6 mm, which is led past the barking separation and the thicker wood chips are fed to the mechanical bark separation.
  • These fractions are combined and the sawdust and light birch bark is sieved out and sorted optically, the accepted fraction of which is clean wood chips and the reject is returned to mechanical bark separation, in which the bark is ground to a smaller size, so that it can be distinguished in the sawdust discharge.
  • Improvement of the cellulose wood chip yield by 5 percentage units improves the profitability of the plant by about FIM 20/m 3 , which represents FIM 3 000 000 p.a. in a plant producing 150 000 m 3 p.a..
  • the effect of the chip size of cellulose wood chips on the sales price varies from case to cases, but at its greatest it too is about FIM 25/m 3 . Together these correspond, in magnitude, to the operating and capital costs of the plant, so that the economy of the method improves substantially.

Landscapes

  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Mechanical Engineering (AREA)
  • Solid Fuels And Fuel-Associated Substances (AREA)
  • Debarking, Splitting, And Disintegration Of Timber (AREA)

Abstract

The object of the invention is a method and equipment manufacturing predetermined low bark content wood chips and a high bark content fuel fraction from wood chips with bark attached, which method includes the following stages: mechanical bark removal treatment (7), in which the bark is removed from the chips and their size is reduced; and pre-cleaning (6, 9, 11) of the flow of chips with bark attached; and final cleaning of the aforesaid wood chip flow from the pre-cleaning, with the aid of an optical separator (10). Before the mechanical bark removal process (7) a thin fraction of the chips is sieved out of the flow of wood chips, and then bypasses the mechanical process (7), which improves the yield and the piece size distribution.

Description

A METHOD AND EQUIPMENT FOR MANUFACTURING PREDETERMINED LOW BARK CONTENT WOOD CHIPS AND A HIGH BARK CONTENT FUEL FRACTION FROM WOOD CHIPS WITH BARK ATTACHED
The object of the invention is a method and equipment for manufacturing predetermined low bark content wood chips and a high bark content fuel fraction from wood chips with bark attached, which method incudes the following stages:
- a mechanical bark removal process, - pre-cleaning of wood chips with bark attached, and
- the final cleaning of the flow of wood chips, with the aid of an optical separator.
The above-mentioned type of manufacturing method is known from the international patent publication WO 93/25324. According to this, the wood chips with bark attached are ground initially either with a special plate grinder, or with a vibrating cone crusher, when the bark separates from the wood chips and the size of the bark particles diminishes. By means of this, the bark can be separated more easily during later separation stages. A grinder or a vibrating cone crusher is followed by pneumatic separation, especially to separate outer birch bark, after which sawdust is removed using a vibrating sieve. The bark content has now dropped to considerably less than 10 %, when the final cleaning can be carried out using an optical sorter. According to the patent, two optical sorters are used in series, but can, however, be replaced by a single more powerful device. The accepted fraction from the second optical sorter is led to grinding and the reject to the fuel fraction.
Equipment that is essentially that described by the application has been built in Kankaanpaa in Finland, the supplier being BMH Wood Technology Oy. In the commercial equipment, a magnetic separator and a pneumatic separator are used in the pre- cleaning to separate metal scrap and stones. Sawdust is removed from the commercial equipment before grinding, and after grinding the vibrating sieve has been replaced by a so-called pocket-roll sieve ( a roller sieve developed especially for sieving sawdust) . In the commercial equipment, a good yield is achieved with a bark content of about 1 %, which is sufficiently clean for the manufacture of certain grades of cellulose. The yield varies between 60 - 70 %, depending on the species of timber and other factors. If cleaner chips are wanted, the yield drops, and correspondingly improves with a poorer level of cleanliness.
The intention of this invention is to achieve a better yield than previously at each corresponding level of cleanliness. The characteristic features of the method according to the invention are presented in the accompanying Patent Claim 1 and the features of corresponding equipment are presented in Patent Claim 8. The distribution values of the wood chip fractions according to the accompanying table are, to a great extent, the point of departure of the invention:
Sieve gap Fraction Clean Wood Bark % of mm remaining wood chips wood in sieve chips in with bark chips
% fraction with bark
0 5,03
2 16,73 79,03 1,96 3,61
4 37,94 89,98 2,72 8,57
6 25,37 85,54 7,15 16,78
8 8,01 74,54 14,83 19,98
10 6,92 69,00 25,51 18,30
It is surprising, that in the smallest fractions (sieve gap 4 mm, or less) , there is not much bark attached to the chips, whereas in chips above this size the proportion of chips with bark attached is considerable. Because mechanical processing in any event reduces the size of the wood chips across the board, it is advantageous to separate this fairly clean part of the wood chips and have it bypass the mechanical processing. There is bark as such even in the smallest chips, but is it loose, and most of it leaves during the separation of the sawdust, which has been moved so that it takes place after the mechanical processing.
In what follows, the invention is illustrated by reference to the accompanying Figures, which show schematically one plant according to the invention and the method used in it.
Figure 1 shows the method according to the invention, as a block diagram. Figure 2 shows equipment according to the invention, as a plant diagram.
In the diagram in Figure 1, the wood chips with bark attached can be considered as having been obtained by conventional methods, using a known cutter. In the first stage of processing, the wood chips are cleaned in pre-separation 3, 4, 5, which comprises among, other things, magnetic devices for removing scrap iron and a pneumatic separator 4, 4' for removing stones and sand. In pre-separation, oversize wood chips are separated by means of disc sieve 5, and in practice are most advantageously led to the fuel fraction, but if necessary they can be led, for example, to a crusher and then back to pre-separation. The fraction accepted in pre-separation 3, 4, 5 is led to thickness sieving 6, which is intended to separate the thin wood chip fraction, generally less than 6 mm, from the part of the flow of wood chips travelling through the thickness sieve. This part is led to the following stage, i.e. past mechanical bark separation 7. Mechanical bark separation can take place by means of either a plate grinder, a crusher, or in a blade ring chipper, which has been shown to be the most advantageous, because it does not defibrate the wood material unnecessarily. The mechanically processed fraction, together with the smaller fraction obtained from the bypass line, is led to pocket-roll sieve 9, which effectively removes the sawdust from the flow of material. After this, the accepted fraction is led to a pneumatic separator, to remove light birch bark, leaves, needles, and other easily airborne particles from the flow of material. After this, the pre-cleaned wood chips already have a bark content of less than 10 %, when it can be led to optical sorter 10, from which wood chips with a bark content of about 1 % can be obtained, even at a large yield. Reject from the optical sorter is led through selection 15 in a regulated manner either to the fuel fraction, or back to mechanical processing. In order to prevent a so-called 'mad cycle', 20 - 100 % is always led to the fuel fraction, and only 80 - 0 % is led to the mechanical processing. Certain species of timber or other conditions will mean that there is not necessarily any benefit from mechanical processing, in which case it is better to lead the reject from the optical sorter directly to the fuel fraction.
The plant diagram, Figure 2, shows cutter 1 and reception funnel 2, in which the wood chips are collected, or into which wood chips from external sources are poured. From here the flow of wood chips is led through magnetic separator 3 to disc sieve 5. Between these there is a pneumatic separator 4', which removes stones and a second pneumatic separator 4, which sucks light birch bark, leaves, and fine dust into the airflow, see also stone store 3.1. A disc sieve 5 removes oversized pieces from the wood chips, which are led to the fuel fraction 13, together with reject from the pneumatic separator. Beneath the disc sieve there is thickness sieve 6, which separates the smallest fraction and the sawdust in it, these being led to mechanical bark separation, going past grinder 7, whereas the rest of this part is led to grinder 7. Experiments have, however, shown that bark can be effectively separated by cutting the chips. The mechanically processed chip fraction obtained from the plate grinder and the thin fraction obtained from the bypass line 8 are led to the Pocket-Roll sieve 9, which removes sawdust and fine bark material from the flow of chips. After the Pocket-Roll sieve, there is a pneumatic separator 11, which removes light birch bark, leaves, needles, and other easily airborne material.
The accepted fraction is led to optical sorter 10, from which a good yield of good quality cellulose wood chips 12 are obtained. The reject is led through selection member 15 either to the fuel fraction 13 or to the grinder 7. Using selection member 15, 0 - 100 % can be taken from the flow of materials into the fuel fraction. It is advantageous to take at least 20 %, to prevent a so-called 'mad cycle' in the process. With certain grades of wood chips part of the material would remain to circulate continuously through the process, unless part of the reject is removed to the fuel fraction. All of the removed rejects are led in the Figure to fuel fraction 13, by means of conveyor 16.
Because the optical sorter uses a pneumatic conveyor, the reject flow is not homogeneous. A divider plate 18 set in the exit area can separate the part with the greatest bark content from the rest of the reject, it then being advantageously led directly to the fuel fraction with the aid of conveyor 19. The figure shows this alternative by broken lines.
The pulverization of the wood is reduced with the aid of the method according to the invention, which increases the cellulose chip yield from the previous yield by 5 - 10 percentage units, while share of the fraction of cellulose chips remaining in the 13 mm particle size perforated sieve increases substantially (by 15 - 35 percentage units) .
In equipment according to the invention, a thickness sieve is used to separate the fraction with the desired value, 4 - 8 mm, for example, thinner than 6 mm, which is led past the barking separation and the thicker wood chips are fed to the mechanical bark separation. These fractions are combined and the sawdust and light birch bark is sieved out and sorted optically, the accepted fraction of which is clean wood chips and the reject is returned to mechanical bark separation, in which the bark is ground to a smaller size, so that it can be distinguished in the sawdust discharge.
Improvement of the cellulose wood chip yield by 5 percentage units improves the profitability of the plant by about FIM 20/m3, which represents FIM 3 000 000 p.a. in a plant producing 150 000 m3 p.a.. The effect of the chip size of cellulose wood chips on the sales price varies from case to cases, but at its greatest it too is about FIM 25/m3. Together these correspond, in magnitude, to the operating and capital costs of the plant, so that the economy of the method improves substantially.

Claims

Patent Claims
1. A method for manufacturing predetermined low bark content wood chips (12) and a high bark content fuel fraction (13) from wood chips with bark attached, which method includes the following stages:
- mechanical bark removal treatment (7) , in which the bark is removed from the chips and their size is reduced, and
- pre-cleaning (6, 9, 11) of the flow of chips with bark attached, into a flow of chips with a bark content of less than
10 % and high bark content rejects, with the aid of pneumatic and mechanical sieving,
- final cleaning of the aforesaid wood chip flow from the pre¬ cleaning, with the aid of an optical separator (10) , to create low bark content wood chips (12) and a fraction with a higher bark content,
- collection of the rejects leaving the process, to create the aforementioned high bark content fuel fraction, characterized in that before the aforesaid mechanical bark removal process (7) a predetermined thin fraction of the chips, for example, pieces less than 6 mm, is sieved (6) out of the flow of wood chips, and then bypasses the aforesaid debarking process (7) .
2. A method according to Claim 1, characterized in that the mechanical bark removal process (7) takes place by means of a grinder, press-rollers, or a crusher.
3. A method according to Claim 1, characterized in that the mechanical bark removal takes place using a blade ring chipper, which cuts the wood chips into smaller pieces, while removing the bar .
4. A method according to Claim 1, characterized in that 20 - 100 % of the aforementioned fraction with a higher bark content obtained from the optical separator (10) is directed to the fuel fraction (13) , and correspondingly 80 - 0 % is returned to the mechanical bark removal process (7) .
5. A method according to Claim 4, characterized in that the optical separator includes a pneumatic conveyor and a division plate (18) , by means of which the flow of chips is divided first into the aforesaid wood chips with a low bark content and wood chips with a higher bark content and further the latter part is divided with the aid of the division plate (18) directly into a fuel fraction and the aforesaid part that is returned.
6. A method according to Claim 1, characterized in that it includes pre-separation (5) before the aforesaid thickness sieving (6) , in which the oversized wood chips, stones, and metals are removed from the wood chips with bark attached.
7. A method according to one of Claims 1 - 5, characterized in that the flow of wood chips from the mechanical bark removal process (7) and the aforesaid thin chip fraction from the thickness sieving (6) are sieved using a mechanical sieve (9) , to remove sawdust as a third reject and using a pneumatic separator (11) to remove light birch bark, leaves, needles, and other airborne material as a fourth reject.
8. Equipment for manufacturing wood chips with a low bark content from wood chips with bark attached, which equipment includes mechanical bark removal devices (7) and pre- separation devices consisting of a mechanical and a pneumatic separator (9, 11) and an optical sorter (10) , characterized in that the equipment includes a wood chip thickness sieve (6) located before the mechanical bark removal devices (7) and a correction line (8) connected to the exit of the thin fraction obtained, by means of which the thin fraction is taken past the mechanical bark removal devices (7) to the pre-cleaning devices (9, 11) .
9. Equipment according to Claim 7, characterized in that the mechanical bark removal devices (7) consist of one or more blade ring chippers, a grinder (7) , a press roller, or a crusher.
EP96934872A 1995-11-01 1996-11-01 A method and equipment for manufacturing predetermined low bark content wood chips and a high bark content fuel fraction from wood chips with bark attached Expired - Lifetime EP0958427B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FI955213 1995-11-01
FI955213A FI98277C (en) 1995-11-01 1995-11-01 A method for producing low-bark wood chips from bark wood chips and corresponding equipment
PCT/FI1996/000586 WO1997016590A1 (en) 1995-11-01 1996-11-01 A method and equipment for manufacturing predetermined low bark content wood chips and a high bark content fuel fraction from wood chips with bark attached

Publications (2)

Publication Number Publication Date
EP0958427A1 true EP0958427A1 (en) 1999-11-24
EP0958427B1 EP0958427B1 (en) 2002-03-20

Family

ID=8544302

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96934872A Expired - Lifetime EP0958427B1 (en) 1995-11-01 1996-11-01 A method and equipment for manufacturing predetermined low bark content wood chips and a high bark content fuel fraction from wood chips with bark attached

Country Status (7)

Country Link
US (1) US6260777B1 (en)
EP (1) EP0958427B1 (en)
AT (1) ATE214751T1 (en)
AU (1) AU7300496A (en)
DE (1) DE69620041T2 (en)
FI (1) FI98277C (en)
WO (1) WO1997016590A1 (en)

Cited By (2)

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Publication number Priority date Publication date Assignee Title
EP2025738A1 (en) * 2007-07-27 2009-02-18 Johannes Schörkhuber Method for manufacturing wood pellets from offcuts
DE102017009414A1 (en) * 2017-10-11 2019-04-11 Ernst Christian Tienes Process for the production of solid fuel moldings

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US6392070B1 (en) 1999-08-10 2002-05-21 Regents Of The University Of Minnesota Birch bark processing and the isolation of natural products from birch bark
FI112041B (en) * 2000-08-02 2003-10-31 Bjarne Holmbom A method for recovering knotweed material from oversized chips
DE10124717A1 (en) * 2001-05-19 2002-11-21 Rolf Hesch Process to recycle furniture and automotive residues by mechanical shredding and pneumatic sorting
FR2905627A1 (en) * 2006-09-13 2008-03-14 Hd Services Sarl Dense wooden piece e.g. wood pellet, manufacturing method, involves bagging wood particles, and aspirating bark particles, which are not disintegrated during drying of bark particles, where drying is made parallel with bagging
ITPG20090070A1 (en) * 2009-12-29 2011-06-30 Eco Pellet Group Srl PROCEDURE FOR THE PRODUCTION OF ECOLOGICAL PELLETS BY MEANS OF CONTROL CHAMBER POSTED IN PRODUCTION PLANTS AND PELLET BAGGING.
US8752779B2 (en) * 2011-08-05 2014-06-17 Forest Concepts, LLC Woody biomass beneficiation system
JP6213283B2 (en) * 2013-03-27 2017-10-18 セイコーエプソン株式会社 Sheet manufacturing equipment
JP2014208925A (en) 2013-03-27 2014-11-06 セイコーエプソン株式会社 Sheet manufacturing apparatus
GB2527544B (en) * 2014-06-25 2017-11-08 Biosci Ltd A method of processing waste material to produce various wood products
CA2989578C (en) 2015-06-15 2023-09-19 Biofuels Technology Llc Systems and methods for use in processing of forest residue
RU2756752C2 (en) * 2018-10-30 2021-10-05 Федеральное государственное бюджетное образовательное учреждение высшего образования "Поволжский государственный технологический университет" Installation for separating birch bark from bast

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RU94046253A (en) * 1992-06-08 1996-10-27 Валтион Текниллинен Туткимускескус (Fi) Method of production of wood chips with low content of bark from whole wood chips
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2025738A1 (en) * 2007-07-27 2009-02-18 Johannes Schörkhuber Method for manufacturing wood pellets from offcuts
DE102017009414A1 (en) * 2017-10-11 2019-04-11 Ernst Christian Tienes Process for the production of solid fuel moldings

Also Published As

Publication number Publication date
EP0958427B1 (en) 2002-03-20
DE69620041D1 (en) 2002-04-25
ATE214751T1 (en) 2002-04-15
US6260777B1 (en) 2001-07-17
DE69620041T2 (en) 2002-11-14
FI98277B (en) 1997-02-14
FI98277C (en) 1997-05-26
FI955213A0 (en) 1995-11-01
AU7300496A (en) 1997-05-22
WO1997016590A1 (en) 1997-05-09

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